Recent developments on portable and wearable electronic devices are requiring minimized power supplier system, namely the battery which can provide high volumetric energy and power density. Electrode stack is a promising design that satisfies the requirements of such type of battery. A stacked battery including a stack of positive and negative electrodes is conventionally known. A separator is provided between the positive and negative electrodes to avoid a short circuit from occurring between said positive and negative electrodes and also to allow sufficient ionic conductivity between negative and positive electrodes. Such a cell including an assembly of stacked electrodes is disclosed for example in patent U.S. Pat. No. 3,907,599 or in patent publication EP 2610945. The assembly of stacked electrodes is connected to an external circuitry via contact tabs protruding from the positive and negative electrodes respectively.
When stacking electrode pieces, people have to face the challenges of terminal tabs design, packing, and followed by manufacturing them.
Traditionally after the stacking process of electrodes, packing tapes are applied around the assembly of stacked electrodes to hold the whole electrode stack. Besides, in order to avoid short circuit between electrode current collector and metallic case of the cell, an insulation foil is placed in-between. Both the packing tape and insulator foil are made of electronic inert polymer. A drawback of such known arrangement is that the risk of electrolyte leakage increases significantly since the insulation foil and the welded cathode tabs are placed under the gasket. Another drawback of such arrangement is that at least two different forms of polymer for the packing tape and for the insulation foil are required. Moreover, it needs people to concern about avoiding displacement of insulation foil from electrodes, the design freedom of contact tabs, etc. In addition, different forms of tape lead to multiple steps during manufacturing process.
It is therefore necessary to propose a new coin cell with stacked electrodes which is less complex and costly to manufacture and which is not subject to the limitations of known stacked cells.